This invention relates generally to a dispensing system for miniature vehicles and more particularly to a dispenser spin-up speed control system.
In dispensing miniature vehicles of various types in space or in the atmosphere, where some form of guidance is required, it is necessary to provide some spin effect to the vehicle in order to insure proper operation of guidance components. Various systems have been studied for providing the spin-up for the dispensing system and two have been found with the potential to accomplish the task.
An electric motor only drive system has been proposed but fails, in that the torque required for the motor to accelerate a reasonably sized dispenser to 20 revolutions per second in 10 seconds, for example, would require a large motor, and hence to cause a reaction torque on the upper-stage vehicle (in a space application) necessating a two-stage nitrogen reaction control system instead of the single stage system described in the invention.
A more acceptable system, for providing spin is a system where the dispenser is run-up and controlled by two driving systems. A toroidal high pressure nitrogen tank and two peripherally located nozzles provide torque to accelerate the dispenser up to speed, with approximately 6.5% tolerance, and a small electric motor which brings the speed to 20 revolutions per second, with in 10 seconds from spin-up start. The electric motor holds the speed of the dispenser to .+-.0.1 revolutions per second.
Each of the peripherally located nozzles is opened by dualized pyrotechnic devices. The nitrogen then "blows down" to depletion, accelerating the dispenser to the near 20 revolutions per second.
This double system (gas-electric) provides substantially the same degree of reliability as a single (electric motor only) system with a two-stage reaction control system in the upper stage. Further, considering the weight variably between the heavier single system and the lighter dual system the dual system is a substantially superior system to the single system.